The present invention relates to a sliding wall arrangement for covered railroad freight cars, wherein the sliding wall sections, which are co-planar in the closed state, are movable, transversely of the car by means of respective hand levers and actuating linkage connected thereto, out of the closing plane into a shifting plane for engagement with running rails on which they can be shifted, by means of rollers in the longitudinal direction of the car, past closed wall sections, in order to clear the opening. A single, rectilinear uninterrupted running rail is provided in the upper stringer of the side wall frame, and the outer lateral surface of the outer longitudinal beam forms the running-on surface for the bottom edge of the sliding wall sections.
In accordance with U.S. Pat. No. 3,828,693, at least two rollers or guide forks, respective to each sliding wall section, are provided on the free ends of levers which are secured to shafts pivotable by means of the actuating linkage for oscillation transversely of the car and, in the floor and adjacent the outer longitudinal beam, brackets are provided which, in swung-out position, have their outside web portions conformingly seated in mating cutouts of the outer beam. These brackets are pivotable transversely of the car by means of levers acting as a parallel guide and coupled, through shafts, to the actuating linkage. The sliding wall sections carry, at their top, running rollers rotatable on supporting arms about horizontal axes and supporting cams cooperating with the rollers or guide forks and, at their bottom, supporting arms on the free ends of which rollers rotatable about vertical axes and guide channels embracing a vertical web plate at the bottom of the longitudinal beam or the brackets are provided. The sliding wall sections are movable from the closing plane into the shifting plane, at the top, by means of the rollers or guide forks and, at the bottom, by means of the brackets.
On their outside, the supporting arms are formed with vertical surfaces which, in the closing position of the sliding wall sections, form a flush closure for the cut-outs of the longitudinal beam, in the running plane of the rollers. Due to this design of the sliding wall sections in accordance with the U.S. patent mentioned above, all sliding wall sections can be made identical so that they are easily interchangeable as to their position, both during assembly and in operation. The sealing of the sliding wall sections against each other is effected, in a well known manner, for example, by means of rubber packing strips. To be able to effect the sealing also by means of metallic labyrinth packings which, in rail vehicle construction and, particularly, in the construction of freight cars, are advantageous, the sliding wall sections must either be guided, in the last phase of their closing motion, obliquely against each other, or they must overlap with their vertical sealing edges. With closures comprising two sliding wall sections, with or without central posts, it has proved advantageous to guide the sliding wall sections, in the last phase of their closing motion, obliquely relative to the longitudinal axis of the car and to the adjacent sliding wall section. In this case, a metallic labyrinth packing can be used in which the sliding wall sections interengage on their front sides. The same arrangement may be used with closures comprising four sliding wall sections and a central post.
With a closure comprising three sliding wall sections which, ordinarily, is designed with a central post, this arrangement cannot be used. For lading reasons, such trisectional sliding walls require opening of the central sliding wall section first. Then, if metallic labyrinth packings are used for sealing the sliding wall sections against each other, the end sliding wall sections must first be brought into closing position and it is only thereupon that the central sliding wall section can be closed. This necessity, however, requires a different design and actuation of the central sliding wall section as compared to the end sliding wall sections.